but we know neither justices souter nor stevens did that. they were both republican employees and went out during president obama's term. life circumstances can drive retirement decisions. so it's really not scientifically predictable or politically predictable. >> do you see any most likely candidates if another seat opens up under president obama? >> you know, i think if president obama, first of all, justice ruth bader ginsburg i think the pressure to replace her with another woman appointee would be enormous. we've made progress in getting a third of the court female and i don't think president obama or any president would want to go backwards on that. so some potential people for justice ginsburg, if you're looking at the likely women, there is kathy rutler the current white house counsel a very accomplished lawyer. caitlin hal igen whom president obama has nominated for the d.c. circuit would be another potential appointee. pamela harris the attorney general of california, very savvy, accomplished, politically savvy and accomplished la